Support for tension structures evidenced in international symposium; fabric wins in Brazil’s sports stadia; mesh “immersion enclosure” brings visitors and birds together.

By Frank Edgerton Martin and Víctor Hugo Roldán

Held April 6–8 in Montevideo, Uruguay, at the Faculty of Architecture, Universidad de Montevideo, the IV Simposio Latinoamericano de Tensoestructuras brought together more than 275 students, faculty, professionals and suppliers of the tension structure industry.

Nicholas Goldsmith, senior principal of FTL Design Engineering Studio, New York City, N.Y., the first speaker, addressed one of the symposium’s main topics with “Skin: Biomembranes in Buildings.” Goldsmith talked about ways to approach design: acoustics, sun cover, water collection, adapting design to an area, and form.

On the same topic of skin, buildings and textile façades, Thomas Dreyfus of Ferrari Textiles (La Tour du Pin, France), discussed recent projects where buildings have been covered completely by Stamisol®, a resistant mesh product that allows views through membrane façades.

Lectures by Mauricio Chivante of Birdair and Hugo Larontonda, project manager, explained the complicated process of erecting the “membrane-tensegrity” cover for the stadium in La Plata, Argentina. The structure, completed last year, had been designed in the early 1980s but construction was delayed for economic reasons. The project is a good example of today’s globalization: the architect was Roberto Ferreira & Associates (Barcelona, Spain), engineering was by Weidlinger Associates Inc. (New York, N.Y.), consultants to the project and supervisor of the fabric roof was Birdair (Buenos Aires, Argentina), and the main contractor was Astilleros de Buenos Aires, with workers from Argentina and South Africa.

Sports facilities are still a hot topic. Speakers Knut Stockhusen (from Schlaich Bergermann und Partner, Stuttgart, Germany) gave a presentation on the 2014 FIFA World Cup Soccer stadium to be constructed in Brazil, and McCormick Fergus (from Buro Happold, London, England) presented a 2012 Summer Olympic Games stadium in London.

The goals achieved at this event were so important that at the meeting of the Red Latinoamericana de Tensoestructuras, several countries entered into a bidding war to host the next symposium. By votes, Chile and the Pontifica Universidad Catòlica de Chile prevailed, and the symposium will not be held after the usual three-year wait, but in spring 2012. Brazil will host the VI Symposio in 2013 at Universidade de São Paulo.

Many goals remain ahead for the Red Latinoamericana de Tensoestructuras, including officially linking to the European-based Tensinet (how this will be done is still unknown), and a better integration among Latin American countries when developing their “Tenso Guides” as a base for construction codes. Currently, in many Latin American countries there are few guidelines for designing and construction in this field, so designers and engineers have to look to North American and European guides.

Attention to sports

Last year, with the announcement of the winner of the venue sweepstakes for the 2014 FIFA World Cup and 2016 Summer Olympic Games, Brazil suddenly bumped up the excitement for sports development in South America. Tensioned fabric will play a significant part of many of these planned new or remodeled stadia throughout that country, which has a culture where soccer is almost a genetic birthright and sports of many kinds are a national passion.

Work has already begun on several of the 17 venues that will house the 2014 World Cup Soccer games. Designed by the German firm Architekten von Gerken, Marg und Partner (GMP), three sports complexes each have new substantial fabric or ETFE elements as part of the design.

Located in the Amazon jungle 1,500km from the sea, Manaus lies at the convergence of the Rio Negro and Rio Solimões that form the Amazon River. The Amazon Sports Complex is an integrated sports park that includes multi-purpose venues and a swimming center. The roof structure is made of mutually supporting cantilevers of hollow core steel girders that also function as rainwater gutters. The roof and façade are clad in translucent, low-e coated fiberglass fabric that reflects heat radiation, helping to cool the building. The stadium will be one of the first to be LEED compliant.

Located in the historic mining city of Belo Horizonte, the third largest city in Brazil, the Mineirão/Mineirinho Complex is a modernization and renovation of a historic stadium that was built between 1963 and 1965 to designs by Eduardo Mendes Guimarães Jr., and Caspar Garetto. The Mineirão Stadium (“Big Miner Stadium”), with its rhythmically spaced concrete ribs, is listed as a national monument. To bring the stadium up to modern standards, GMP Architekten and Schlaich Bergermann & Partners substantially upgraded the infrastructure and capacity, as well as added an ultra-lightweight ring cable structure covered by a translucent membrane with solar cells that provide shade and generate electricity.

Designed and completed in 1974 by Ícaro Castro Mello, the Mané Garrincha Stadium has been reworked and renamed the National Stadium for the 2014 FIFA World Cup Soccer games. A new lower tier and the completion of an existing upper tier fragment have been designed by Castro Mello’s son Eduardo, and a surrounding esplanade with a “forest of supports” has been designed by GMP Architekten with Schlaich Bergermann & Partners adding a double-layer suspended roof. The roof’s double layer of translucent membranes follows a circular geometry and is held in place by a concrete compression ring at the perimeter; a retractable inner roof concentrates at a central hub held in place by massive cabling in a structural concept similar to the spokes of a bicycle wheel.

The Place of Birds

Over the centuries, zoos have evolved from private collections of exotic animals to powerful advocates for species conservation and environmental education. Located outside of Buenos Aires, Argentina, Parque Temaikèn is one of the most progressive zoos in Latin America. Like many of today’s environmental centers, Temaikèn fosters a love of nature by bringing visitors face to face with it. To achieve this intimacy, the animals need to be as free to roam as their human counterparts.

In 2004, Temaikèn began to redesign its bird exhibits with “immersion enclosures” that could bring visitors close to plants and birds in a seamless connection with the sky, an onsite lake and the changing weather. Yet with the need for animal containment and the need to keep out predators, the challenge was to find a way to exhibit birds without creating a sense of confinement.

Jakob® Inox, Swiss manufacturer of cable and netting systems, offers a webnet rope and mesh product system that is proving an ideal solution for contemporary zoos. Because of its transparency, flexibility and ability to cover large volumes, Jakob’s Inox Line Webnet product is now part of aviary construction at zoos in cities such as Dublin, Ireland; Geneva and Bern, Switzerland; Kraków, Poland and Hannover, Germany. Temaikèn’s new 2.4-hectare exhibit, “The Bird’s Place,” showcases 200 species of birds and associated plant species in four main aviaries tailored for the Americas, Eurasia, Oceana and Africa.

For each region, the exhibit’s designers selected bird species based on their habitat strata: terrestrial, aquatic, bush birds and treetop nesters. The height of the netting and arches facilitates these layered habitats so the exhibit achieves a diversity rarely found in contained settings.

Representing Eurasia, Oceana and Africa, the Great Aviary is a linear structure supported by three arches with a 12m height. Each region is represented in areas of roughly 900m2. In studying the patterns of bird flight at the higher strata, the designers widened the arches at the top of the aviaries, swaying them outward to allow more range. While these flowing arcs make a sculptural statement when approaching the aviary, the netting stretched between them is virtually invisible. The overall effect is the lightness of a veil rather than a cage.

Only 1mm thick and strung in a 30mm diamond pattern, the Webnet mesh breaks down the visual barriers between inside and outside. Visitors move freely in the pavilions with the sense that both they and the wildlife are outdoors in a nature preserve or hiking trail. But of course, birds and human visitors meet in a much more contained space where the zoo designer’s skills of forced perspective, controlled vistas and unfolding views evoke whole ecosystems at the scale of an urban park. To accommodate smaller birds, the designers created smaller passerines in webbed enclosures set alongside visitor paths.

The Foundation does more than just operate this bio-park. On a broader scale, it operates the Natural Reserve in the Argentinean Province of Misiones. This habitat area works as a “biological shock absorber” for the nearby Teyú Cuaré Provincial Park. The Foundation also runs extensive education and research programs along with a Center for Reproduction of Species that operates animal rehabilitation and reproduction programs, supporting both species conservation and the work of authorities governing the illegal trafficking of animals.

Since opening in the summer of 2009, The Place of Birds has attracted more than half a million visitors and received high rankings in visitor satisfaction surveys. In 2010, the project won an exhibit award from the Association of Zoos and Aquariums, an international organization that oversees member accreditation, conservation and management.

Frank Edgerton Martin is a contributing editor for Fabric Architecture and regularly writes about landscape design, campus and urban planning and sustainable landscape issues. He provided the article, The Place of Birds.
Based in Mexico City, Mexico, Víctor Hugo Roldán is a contributing editor for Fabric Architecture magazine and is principal architect of his own firm Velarias DRV. He provided the report on the international symposium on tension structures.